scholarly journals Study of Combustion Characteristics of Carbon Particles Clouds

2015 ◽  
Vol 16 (1) ◽  
pp. 210-216
Author(s):  
S. G. Orlovska
Keyword(s):  
Mass Concentration ◽  
Fine Particles ◽  
Equal Mass ◽  
Coarse Particles ◽  
Burning Time ◽  
Carbon Particles ◽  
Coal Particles ◽  
Surface Burning ◽  
Temperature Heat ◽  
The Mean

High temperature heat and mass transfer and chemical kinetics are modeled in polydisperse cloud of coal particles taking into consideration reactions in pores and Stefan flow at the surface. Burning characteristics are calculated of bimodal aerosol, with the assumption of equal mass concentration of two fractions with two or three-fold difference between the mean particles diameters. It is shown that ignition delay of coarse particles in bimodal aerosol is significantly less than that of equal size particles in monodisperse aerosol. Also a burning time of fine particles is substantially less in bimodal aerosol. It is demonstrated that burning temperature is higher in case of bimodal aerosol in comparison with monodisperse one.

scholarly journals Properties of Particulate Matter in the Air of the Wieliczka Salt Mine and Related Health Benefits for Tourists

2022 ◽  
Vol 19 (2) ◽  
pp. 826
Author(s):  
Karolina Bralewska ◽  
Wioletta Rogula-Kozłowska ◽  
Dominika Mucha ◽  
Artur Jerzy Badyda ◽  
Magdalena Kostrzon ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Mass Concentration ◽  
Fine Particles ◽  
Health Benefits ◽  
Coarse Particles ◽  
Salt Mine ◽  
Health Resort ◽  
Atmospheric Air ◽  
The Mean ◽  
Internal Sources

This study aimed to evaluate the mass concentration of size-resolved (PM1, PM2.5, PM4, PM10, PM100) particulate matter (PM) in the Wieliczka Salt Mine located in southern Poland, compare them with the concentrations of the same PM fractions in the atmospheric air, and estimate the dose of dry salt aerosol inhaled by the mine visitors. Measurements were conducted for 2 hours a day, simultaneously inside (tourist route, passage to the health resort, health resort) and outside the mine (duty-room), for three days in the summer of 2017 using DustTrak DRX devices (optical method). The highest average PM concentrations were recorded on the tourist route (54–81 µg/m3), while the lowest was in the passage to the health resort (49–62 µg/m3). At the same time, the mean outdoor PM concentrations were 14–20 µg/m3. Fine particles constituting the majority of PM mass (68–80%) in the mine originated from internal sources, while the presence of coarse particles was associated with tourist traffic. High PM deposition factors in the respiratory tract of children and adults estimated for particular mine chambers (0.58–0.70), the predominance of respirable particles in PM mass, and the high content of NaCl in PM composition indicate high health benefits for mine visitors.

scholarly journals Study of Ignition and Combustion of Two-Fraction Coal-Air Suspension

2018 ◽  
Vol 63 (4) ◽  
pp. 370
Author(s):  
S. G. Orlovskaya ◽  
V. V. Kalinchak ◽  
O. N. Zuj ◽  
M. V. Liseanskaia
Keyword(s):  
Fine Particles ◽  
Equal Mass ◽  
Critical Parameters ◽  
Gas Temperature ◽  
Carbon Particles ◽  
Air Suspension ◽  
Temperature Heat ◽  
Mass Fractions ◽  
Different Temperatures ◽  
Ignition And Combustion

A two-fraction dust-air mixture is the simplest example of polydisperse suspensions. We aim to study the characteristics of ignition and combustion of a two-fraction suspension of carbon particles in air at different temperatures. The main characteristics of the dispersed fuel combustion are the ignition delay, burning temperature and time, and critical parameters (temperature, diameters of particles, and mass concentrations) corresponding to the fuel ignition and extinction. The high-temperature heat and mass transfer and chemical kinetics are modeled for a two-fraction particles-gas suspension (diameter of fine particles 60 мm and for that with coarse particles 120 мm) with equal mass fractions. The gas temperature is varied in the interval between 1100 K and 1500 K.

Study on Concentration Characteristics of TSP, PM10 and PM2.5 in Harbin

2013 ◽  
Vol 777 ◽  
pp. 416-419
Author(s):  
Li Kun Huang
Keyword(s):  
Mass Concentration ◽  
Fine Particles ◽  
Atmospheric Particles ◽  
Secondary Standard ◽  
Coarse Particles ◽  
Concentration Characteristic ◽  
The Eu

In order to investigate the concentration characteristic of atmospheric particles, TSP, PM10 and PM2.5 were collected in July 2008 to June 2010. This study investigates the mass concentration of atmospheric particles in each month. The results show the three particle concentrations reached the lowest value in July, while the peak in January. Compared with the national secondary standard, TSP and PM10 were exceeded in January, February, March, April, November, and December and PM2.5 concentrations is above 2 to 8 times of the EU standard (15 μg/m3). Fine particles (PM2.5) and coarse particles (PM2. 5-10) are major component of atmospheric particles. The mass concentration of atmospheric particles on day is higher than at night in major months and lower in May and June. However, it is not obvious in July, August and September.

Polycyclic aromatic hydrocarbons (PAHs) in fine and coarse particles

2013 ◽  
Vol 12 (1) ◽  
pp. 63-70
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Fine Particles ◽  
Gas Chromatography Mass Spectrometry ◽  
Diagnostic Ratios ◽  
Coarse Particles ◽  
Polycyclic Aromatic ◽  
The Mean ◽  
Short Time

<p>About 140 samplings of fine and coarse particles were gathered during the year 2006 in Kozani that represent an urban area surrounded by opencast coal mining. A low volume dichotomus sampler has been used to trap suspended particles. The filters used were teflon, which are ideal for analysis in the determination of PAHs. The determination of Polycyclic Aromatic Hydrocarbons (PAHs) has been carried out by the use of the analytic technique of large volume injection and gas chromatography – mass spectrometry (LVI - GC/MS). The extraction of substances has been made in a two stage procedure, firstly with agitation in a magnetic shaker and secondly by the use of ultrasonic bath. This technique has given high recoveries of PAHs, in short time intervals. The mean daily concentrations of fine particles varied from 4 to 48 μg m-3 and annual mean was 16 μg m-3. The mean daily concentrations of coarse particles respectively varied from 2 to 67 μg m-3 with 23 μg m-3 annual mean concentration. The ΣPAH concentrations for fine samples were 4.80 ± 7.06 ng m-3 and for coarse samples were 1.36 ± 1.59 ng m-3. The mean B[a]Py concentration for fine particles was 0.38 ng m-3. Finally, diagnostic ratios were used to characterize and identify PAHs emission source in this study.</p>

Observational Study on Atmospheric Particles Mass Concentration in Fushun in China

2012 ◽  
Vol 518-523 ◽  
pp. 1580-1585
Author(s):  
Yang Feng Wang ◽  
Yan Jun Ma ◽  
Zhong Yan Lu ◽  
Ning Wei Liu ◽  
Yun Hai Zhang ◽  
...  
Keyword(s):  
Wind Speed ◽  
Mass Concentration ◽  
Fine Particles ◽  
Dilution Effect ◽  
Quality Standard ◽  
Average Concentration ◽  
Atmospheric Particles ◽  
Concentration Data ◽  
Daily Average ◽  
The Mean

The variations of the atmospheric particles mass concentration, their pollution condition, and their relationships to visibility and wind speed have been studied by using the continuous concentration data of monitoring instrument GRIMM180 from Fushun air component monitoring station in 2009. The results show that the mean mass concentrations about PM10 and PM2.5 are respectively 0.073 ㎎/m3 and 0.048 ㎎/m3, and their daily average concentration has a large variation range. The ratio above air quality standard about PM10 daily average concentration is 5.9%, and the atmospheric particles exist mainly in the form of fine particles. The atmospheric particles mass concentration and the visibility show negative correlation, and the finer the particles are, the more they affect visibility. In general, the atmospheric particles mass concentration will gradually decrease with the rising of the wind speed. When the wind speed is more than 1.0 m/s, there is an obvious dilution effect on particles mass concentration, and when larger than 4.5 m/s, the relevance is not highly apparent.

scholarly journals Size distribution and chemical composition of airborne particles at Akrotiri Research Station, Crete, Greece

2013 ◽  
Vol 12 (1) ◽  
pp. 54-62
Keyword(s):  
Particulate Matter ◽  
Mass Concentration ◽  
Fine Particles ◽  
Sampling Period ◽  
Airborne Particles ◽  
Research Station ◽  
Aerodynamic Diameter ◽  
Concentration Peak ◽  
The Mean ◽  
Ambient Levels

Particulate matter measurements were performed at the Akrotiri research station on the island of Crete (Greece) using an 8-stages Andersen non-viable impactor. The main purpose of the current work was to measure the ambient levels of PM10 particulate matter as well as the concentrations of metals and ions in 8 different PM size fractions with aerodynamic diameter cutoff at 9, 5.8, 4.7, 3.3, 2.1, 1.1, 0.7, 0.4 and a back-up filter for particles below 0.4 μm. The mean PM10 concentration during the first sampling period of August 2007 was equal to 28.2 ± 14.0 μg m-3 (10/08/2007 – 26/08/2007), whereas during the second sampling period (09/07/2008 – 16/07/2008) was 40.2 ± 16.9 μg m-3. Moreover, mean concentrations of PM2.1 particulate matter were measured on the average equal to a 41.0 % and 37.2 % of PM10, respectively for the two corresponding sampling periods. The measurements showed high concentration of fine particles (with aerodynamic diameter less than 0.9 μm), whereas the mass concentration peak was located at an aerodynamic diameter close to 4 - 5 μm. Sulphate was the most abundant anion PM10, whereas sea production ions, such as chlorine, sodium and nitrate, were also in elevated concentrations presented. In addition, the crustal element Fe was in higher concentrations in comparison to the measured heavy metals.

scholarly journals Particle size grouping method as a control system of efficiency flotation process on the example of coal

2020 ◽  
pp. 33-33
Author(s):  
Dorota Kalisz ◽  
Kamil Kuglin ◽  
Anna Młynarczykowska
Keyword(s):  
Particle Size ◽  
Fine Particles ◽  
Flotation Kinetics ◽  
Particle Volume ◽  
Initial Size ◽  
Flotation Process ◽  
Carbon Particles ◽  
Coal Particles ◽  
Total Particle ◽  
Size Of Particles

Agglomeration of coal particles during flotation can be analysed with the Particle Size Grouping (PSG) method. Numerous experiments were carried out to theoretically explain the effect of carbon particles agglomeration, but the result still remains incomplete. In this paper the PSG method was used to analyse agglomeration groups of carbon particles of initial size 100-400 ?m, maintaining the total particle volume. The size of particles population with definite radius and density was determined for 1 Mg coal. The influence of density and size of particles with given mixing energies and parameter ? on agglomeration was analysed. It was stated that the size of the particles had an effect on their agglomeration. In the analysed cases the dimensionless parameter of collision turbulence t* needed for particles agglomeration in particular size groups was importantly shorter for particles of initial size 300 and 400 ?m. The change of the mixing energy did not have influence on the agglomeration of coal particles. The theoretical analyses based on computer calculations were supplemented by the analyses of the coal flotation process on an aqueous model. Experiments lied in introducing a foaming agent in the form of aqueous solution of hexanol which, without changing pH of the pulp, lowered surface tension value, and consequently increased the dispersion of air in the suspension. The experimental results were presented in the form of flotation kinetics curves. Fine particles 100-200?m. turned out to be best for flotation, unlike coarse 400-500 ?m.

scholarly journals Contribution of Fine Particles to Air Emission at Different Phases of Biomass Burning

Atmosphere ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 278 ◽  
Author(s):  
Niloofar Ordou ◽  
Igor E. Agranovski
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Fine Particles ◽  
Combustion Process ◽  
Coarse Particles ◽  
Biomass Smoke ◽  
Smoke Particles ◽  
Air Emission ◽  
Entire Duration ◽  
Diffusion Properties

Particle size distribution in biomass smoke was observed for different burning phases, including flaming and smouldering, during the combustion of nine common Australian vegetation representatives. Smoke particles generated during the smouldering phase of combustions were found to be coarser as compared to flaming aerosols for all hard species. In contrast, for leafy species, this trend was inversed. In addition, the combustion process was investigated over the entire duration of burning by acquiring data with one second time resolution for all nine species. Particles were separately characterised in two categories: fine particles with dominating diffusion properties measurable with diffusion-based instruments (Dp < 200 nm), and coarse particles with dominating inertia (Dp > 200 nm). It was found that fine particles contribute to more than 90 percent of the total fresh smoke particles for all investigated species.

scholarly journals Ambient Particulate Matter Air Pollution in Mpererwe District, Kampala, Uganda: A Pilot Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Stephan Schwander ◽  
Clement D. Okello ◽  
Juergen Freers ◽  
Judith C. Chow ◽  
John G. Watson ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Pilot Study ◽  
Fine Particles ◽  
Airborne Particulate Matter ◽  
Personal Exposure ◽  
Ambient Air ◽  
Combustion Products ◽  
Carbonaceous Aerosol ◽  
Coarse Particles

Air quality in Kampala, the capital of Uganda, has deteriorated significantly in the past two decades. We made spot measurements in Mpererwe district for airborne particulate matter PM2.5(fine particles) and coarse particles. PM was collected on Teflon-membrane filters and analyzed for mass, 51 elements, 3 anions, and 5 cations. Both fine and coarse particle concentrations were above 100 µg/m3in all the samples collected. Markers for crustal/soil (e.g., Si and Al) were the most abundant in the PM2.5fraction, followed by primary combustion products from biomass burning and incinerator emissions (e.g., K and Cl). Over 90% of the measured PM2.5mass can be explained by crustal species (41% and 59%) and carbonaceous aerosol (33%–55%). Crustal elements dominated the coarse particles collected from Kampala. The results of this pilot study are indicative of unhealthy air and suggest that exposure to ambient air in Kampala may increase the burden of environmentally induced cardiovascular, metabolic, and respiratory diseases including infections. Greater awareness and more extensive research are required to confirm our findings, to identify personal exposure and pollution sources, and to develop air quality management plans and policies to protect public health.

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